How have you applied state managers in terms of architecture and usage practices?

In frontend architecture, state managers are used for centralized control of the application's state, which simplifies scaling and maintaining the code. I usually separate global and local state: global — through Redux, MobX, or Context API for data shared across many components; local — through useState or useReducer.

Practices:

• Keep the state minimally necessary, avoiding excessive storage.
• Use selectors and memoization to optimize renders.
• Separate the logic of state updates into actions and reducers (in Redux), which improves testability.
• For asynchronous operations, apply middleware (redux-thunk, redux-saga).

Example with Redux:

// action
const increment = () => ({ type: 'INCREMENT' });

// reducer
function counter(state = 0, action) {
  switch (action.type) {
    case 'INCREMENT':
      return state + 1;
    default:
      return state;
  }
}

// usage in component
const count = useSelector(state => state.counter);
const dispatch = useDispatch();

<button onClick={() => dispatch(increment())}>Increment</button>